1. Field
Apparatuses consistent with exemplary embodiments relate to a lens barrel and an optical apparatus.
2. Description of the Related Art
Recently, as the sizes of imaging apparatuses, such as cameras, reduce, demands for small optical apparatuses are increasing. An example of optical apparatuses, used as a component of a camera, may be a so-called zoom lens by which a user may freely change a focal length. A zoom lens may include therein a mechanism for moving lens groups and a mechanism for supporting and moving movable groups generally arranged inside a lens barrel. In detail, a zoom lens may include a lens barrel (which may be also called as a zoom lens barrel or a zoom barrel) that includes a cam frame having a cam groove, a fixed frame having a straight guiding groove, and a movable frame having a driving pin assembled to both the cam groove and the straight guiding groove.
Regarding the lens barrel, because the straight guiding groove in the fixed frame and the cam groove in the cam frame are arranged to cross each other and the driving pin of the movable frame is assembled to both the straight guiding groove and the cam groove crossing each other, the driving pin needs to have a certain size or to be larger than the certain size to ensure that the driving pin has sufficient strength to drive the cam frame and the fixed frame. Therefore, it is necessary to increase the width of the straight guiding groove or the cam groove along with the increasing size of the driving pin. Thus, additional spaces may be required at the outer wall of the fixed frame or the cam frame.
Furthermore, the cylindrical outer wall including a straight guiding groove, such as the fixed frame, may be integrated as a single element to secure sufficient strength for preventing deformation of the straight guiding groove when a lens barrel is dropped on the floor. In other words, if there is a cut portion formed by cutting a portion of the outer wall in the lengthwise direction thereof, it may be difficult for a lens barrel to have necessary strength.
In addition, it is also necessary to accommodate portions other than the straight guiding groove of a cylindrical outer wall. However, it might also be difficult to accommodate because of the size reduction of a lens barrel.